Wait!
Also, at this point in the year, I REALLY recommend that you just wait until January to do your mileage runs. If you're starting from zero anyway, you're shooting yourself in the foot a bit down the road -- I'll explain:
Elite qualification works like this on most carriers: Fly 25k miles anytime between 1/1/2007 and 12/31/2007 to earn Silver Elite status for the period 1/1/2008 through 2/28/2009. In practice, even though you are earning your status in the current year for the next elite year, the airline recognizes your new status as soon as you earn it and "comps" you the remainder of the current elite year.
So, if you earn DL silver before 12/31/2007, your elite status is valid only through 2/28/2009. However, if you earn DL elite status in January or February 2008, you get the rest of the elite year (1/1/2008 to 2/28/2009) "comped" and have DL Silver all the way through 2/28/2010!
So for the same miles, flown one month later, you get the status for another entire year. Plus, since you'll be travelling a lot next year, those elite qualifying miles will build on what you do in Jan/Feb to take you to Gold rather than simply requalify you for Silver.
If that's confusing let me know.
FT veterans -- if I've screwed up my explanation of the Jan/Feb thing, chime in.
peace,
~Ben~